The Super 8 Motel was evacuated of 52 guests and staff on Tuesday morning. Five people were taken to hospital in unstable condition, while 26 were described as stable.

Here is a primer on carbon monoxide poisoning and how to protect yourself.

What is carbon monoxide?

Carbon monoxide — or CO — is a colourless gas with no taste or odour.

It is generated from burning fuel such as wood, oil, natural gas, coal, propane, or gasoline. The risk of CO poisoning is higher in the winter, and the Ontario Association of Fire Chiefs also warns that carbon monoxide threats are present in almost 90 per cent of all homes. It is frequently referred to as a silent or invisible killer.

How many people does carbon monoxide kill?

According to the Ontario Association of Fire Chiefs, carbon monoxide poisoning claims the lives of more than 50 people each year in Canada. Hundreds more are sent to hospital each year, resulting in some form of permanent disability.

New York State’s Department of Health describes carbon monoxide poisoning as the “leading cause of death due to poisoning in the United States.”

What are the symptoms of carbon monoxide (CO) poisoning?

Breathing in carbon monoxide results in your body carrying less oxygen in your blood. Health Canada states online that CO poisoning can “cause health problems before you even notice that it’s present.”

Symptoms depend on the level of carbon monoxide exposure.

At low levels, a person can experience headaches, shortness of breath, tiredness, muscle weakness, and loss of function in a body part such as a limb.

High levels of CO exposure — or even low levels of exposure over a long period of time — can cause impaired vision, chest pain, dizziness, and trouble formulating thoughts.

Winnipeg’s Fire Paramedic Chief John Lane told Global News that no one from this particular incident required intubation or resuscitation.

Very high levels of exposure can cause seizures, coma, or death.

How much CO is too much CO?

According to the U.S. Consumer Product Safety Commission (CPSC), the effects of CO depend on the concentration, length of exposure and an individual’s health.

The concentration of CO in the air is measured in parts per million (ppm).

While most people will not experience any symptoms from prolonged exposure to CO levels between 1 and 70 ppm, some heart patients may experience an increase in chest pain.

The CPSC says as CO levels increase and remain above 70 ppm, symptoms become more noticeable and can include headache, fatigue and nausea.

According to the CPSC, a sustained CO concentration above 150 ppm may cause disorientation, unconsciousness and death.

WATCH: 46 people treated for carbon monoxide exposure following an incident at a Super 8 motel in Winnipeg, MB

The effects of carbon monoxide on pets

Carbon monoxide exposure also poses a significant danger for pets.

According to Dr. Gina Bowen, director of veterinary services at the Winnipeg Humane Society, CO affects animals the same way it affects humans.

“The problem with animals or pets is that they spend more time in the home than people do, and so if there’s a carbon monoxide leak in the home they are often being exposed to it for longer periods of time than people are,” she said.

Additionally, Bowen says because pets are lower to the ground where CO accumulates, they may experience adverse effects before humans.

Bowen says if your dog looks weak, is staggering or collapses, it may be a warning sign.

With cats, owners may notice their pet is looking lethargic, wobbly or may begin to pant.

Bowen says if you think your pet may be suffering from CO poisoning, you should get them into the fresh air immediately.

She says emergency personnel will provide the animal with oxygen, and may administer fluids for shock by I.V.

“But there is no medicine that you can give that’s an antidote for carbon monoxide poisoning,” she said. “It’s just supporting the pet and trying to give them as much oxygen as they can so that their hemoglobin can do what it needs to do and then waiting for the effects of the carbon monoxide gas to wear off.

What can people do to protect themselves?

Health Canada says every home should have at least one carbon monoxide alarm and a smoke alarm. Smoke alarms can only warn homeowners about fire and not the presence of CO, so it is important to install both.

Carbon monoxide alarms can be bought at most hardware stores. Test them regularly and keep an eye on when they should be replaced by noting the installation date on the alarm.

If your CO alarm alerts you to a leak, Health Canada recommends the following:

Do not try to find the source of the leak

Evacuate the home immediately, and seek fresh air

Call 9-1-1 once you’re outside

Only re-enter your home once a professional has fixed the issue.

WATCH: Signs you may have been exposed to carbon monoxide

How can people prevent carbon monoxide leaks?

Health Canada says homeowners should regularly maintain fuel-burning appliances and should have a professional regularly inspect appliances such as fireplaces, furnaces, gas stoves, and water heaters.

The health agency also recommends examining appliances that use propane and natural gas, such as stoves, heaters, and fridges. Check for leaks, cracks, tears, breaks or corrosion in tubes, blocked vents, and faulty connections to gas lines.